MAR-ee-am
The emphasis is on the first syllable, "MAR".
Here's a breakdown:
* MAR: Like the word "mar"
* ee: Like the word "see"
* am: Like the word "am"
Note: The pronunciation can vary slightly depending on the language and region. For example, in some Arabic dialects, the "a" sound in "Mariam" might be pronounced closer to "ah."